I felt it 1st. A low throbbing hum vibrating through my sternum taken up by the bones at the back of my skull. My eyes were on the pad when the lights vanished. Air moved through the tunnel toward me and the force of it increased swiftly. I searched it for what it could tell me but it held no odors I could detect. Cool, cooling; with a sudden increase in force it kicked me back like a great boot.
        I staggered, nearly lost the pad but gripped it tightly and found its screen in time to see the mapping there seize and squiggle into meaningless lines, then dots, of green and red before it blanked. An instant later the screen exploded.
        I dropped the pad, then dropped myself searching for it on the stone floor of the tunnel I could no longer see.
        My hand brushed the pad and it burned. I drew back. Wind pushed me to the wall where I crouched.